Which sentence is in the passive voice?
a. the librarian is now reading a story to the children.
b. in the middle of the night, the mother calmed the baby by rocking him.
c. some penguins waddled across the glacier.
d. the role has been performed by several actors.

The correct answer is D. The role has been performed by several actors. This is because all other options use active forms. Active voice of the last example would be "Several actors have performed the role".

C. How human beings and other forms of life were created.

Explanation:

According to the given passage from the Popul Vuh, Vuh, a sacred text of the Maya civilization about the creation of the Earth, it is narrated that Heart of the Sky spoke with Sovereign and Quetzal Serpent and they decided to bring together their words and thoughts and with that they created the earth, humans and other life forms.

Therefore, the main idea that the passage describes is how human beings and other forms of life were created.